With the increasing success of home appliance systems for carbonated beverages such as beer, there is an increasing need for safe and easy to handle containers guaranteeing an optimal storing capacity for the beverage in terms of quality maintenance and shelf life. As an answer to the mentioned needs, containers have been developed comprising an outer shell having a neck portion defining a first access opening and a flexible inner bag having a neck finish defining second access opening. Such containers are generally known as bag-in-box containers.
To adequately seal the openings while allowing access thereto for dispensing a fluid from the container, it is known to use valve assemblies that can be actuated by dispensing means provided in the home appliance systems. However valve assemblies are expensive and consist of several parts of different materials, rendering the valve assembly difficult to recycle. To overcome the above inconveniences, the home appliance systems are provided with dispensing means comprising valve assemblies, while the containers are provided with a closure comprising an access port where through the dispenser means can be introduced in the container.
WO 89/07575 discloses an assembly of a closure and a bag-in-box container, comprising two distinct sealing members, a first sealing member in the form of a sheet provided on the neck finish of the inner bag and as such sealing the access opening defined by said neck finish. A second sealing member in the form of a sheet is applied on the outer surface of the closure and covers both access ports defined therein. A drawback of this known assembly is that it can not be combined with the use of a closure having an access port that in a fixed position of the closure on the container extends into the access opening of the inner bag as in that case, the concerning sealing member would be broken.
Another drawback of a sealing member according to WO 89/07575 is that is has to be removed or pierced to gain access to the container and inner bag. This seriously limits material choice for the sealing members that need on one hand to fulfil a sealing function and on the other hand to be such that no parts can fall off during piercing of the member since such parts can fall into the liquid stored in the container.
A sealing member according WO 89/07575 has further the inconvenience in that it is difficult to apply on the neck finish of the inner bag once this is applied in the outer shell. Indeed, the access opening of the neck portion of the outer shell limits freedom to handle. This inconvenience is very pertinent when the inner bag and outer shell are assembled in a preform stage and consecutively blow moulded together. This method for manufacturing the container includes maintaining the access port of both the inner bag and the outer shell open at the time of assembling both parts, since the access openings are needed to insert air therein during blow moulding.
Given the above drawbacks and inconveniences, it is now an objective of the present invention to provide an assembly of a container and a closure comprising sealing means that allow design flexibility with regard to both the container and the closure, in particular of the access openings and access ports thereof.
It is a further objective of the present invention to provide a container of the bag-in-box type with an efficient overpressure relief system.
It is generally known that containers for storing carbonated beverages necessitate an overpressure relief system. Such an overpressure relief system has the aim to prevent uncontrolled burst of the container or an uncontrolled ejection of a valve or closure fixed thereto. Existing overpressure relief systems included containers having weakened spots in their body so as to allow a controlled burst in case of overpressure of the use of overpressure valves. With the increasing interest in home appliances, containers with weakened spots in their body have become undesirable, while valves are considered as expensive and as such also undesired. Accordingly, overpressure relief systems have been incorporated in the closure of containers.
Overpressure release systems are described in the art. For example EP-A-1 614 636 and U.S. Pat. No. 5,328,063 both disclose a closure comprising a mount piece that is snap fitted on a container and defining an outflow opening thereof. Centrally in the outflow opening is provided a stem that is an integral part of the mount piece. The closure further comprises a closure cap fixed to the mount piece, the closure cap comprising a flexible diaphragm sealing an outlet of the container and having a free edge that engages the stem. When overpressure occurs in the container, the flexible diaphragm deforms and an opening is created between the stem and the free end of the diaphragm, thereby allowing overpressure relief.
A drawback of the prior art closures incorporating an overpressure relief system is that the essentially comprise a flexible diaphragm, which clearly limits design options with respect to access control by example given piercing. Another drawback is that said closures comprise different materials, in particular a rigid portion for the fixation of the closure to the mount piece of container and a flexible portion for allowing overpressure relief. Hence, the manufacturing and recycling of the known closures is relatively complicated and expensive.